Improved Sliding Mode-Active Disturbance Rejection Control of Electromagnetic Linear Actuator for Direct-Drive System

The electromagnetic linear actuator is used as the core drive unit to achieve high precision and response in direct-drive actuation system. In order improve performance control accuracy of unit, an improved sliding mode-active disturbance rejection (ISM-ADRC) method was proposed. A motor model established based on LuGre dynamic friction. position loop adopts integral traditional mode extended state observer, current PI control. stability system verified Lyapunov theory. nonlinear dilated observer effectively observe velocity information while estimating compensating internal external uncertainty perturbations. At same time, saturation function sat(s) replace sign(s) introduce power displacement error variable. law further improves speed controller reducing jitter inherent conventional mode. Simulation experimental data show that proposed reduces 8-mm step time by 21.9% steady-state less than 0.01 mm compared with sliding-mode control, has 49.4% adjustment for abrupt load changes more robust different loads noise.